This invention relates generally to adhesive tape applicators, and more particularly to applicators for applying tape to the components of a frame or a sash for glazing and to the bars of a muntin.
In conventional windows, doors, skylights and the like, glazing tape is commonly used to seal and secure the glazing to the frame or sash into which it is installed. The tape typically includes a high tack adhesive disposed on both sides of a foam carrier, and a release liner that covers the adhesive on one side of the tape. The release liner remains in place until installation of the glass, at which time it is removed. The side of the tape without the release liner is secured to a glazing leg on the frame or sash member. The side with the release liner faces away from the glazing leg and is exposed. When glazing, the release liner is removed from the tape and the glass is secured to the glazing tape on the glazing leg.
The use of such glazing tapes permits rapid assembly of doors, windows and skylights and provides a low-cost, secure seal. Such glazing tapes are particularly commonly used with frames or sashes formed of an extruded plastic or vinyl, although these tapes can also be used with aluminum frames, wooden frames and the like. A typical glazing tape used for such applications can be obtained from Venture Tape Corp. under the product designations VG100 series and VG300 series (Venture glazing tape). Such tapes typically are provided on a roll having a central cardboard core about which the tape is wound, and are available in any desired width in the range from about xc2xcxe2x80x3 to about 3xe2x80x3.
Colonial-style or divided lite windows and doors are a very popular feature in the domestic housing market. However, manufacture of such windows and doors is very labor intensive and consumes large amounts of energy, because of the many individual pieces of glass that must be separately mounted into the door frame, window frame or sash. To reduce energy and labor costs, manufacturers have developed different techniques to provide the appearance of a divided lite or colonial-style window or door. One recent development, and one that is the most realistic-looking, is the use of a window or door grill or muntin which is affixed to the exterior or interior of a glass pane, or insulated glass unit. This grill or muntin provides the appearance of a colonial or divided lite window or door when in fact the window or door actually comprises a single glass unit. Such grills or muntins are inexpensively made and affixed to the outer or inner surface of a window or door.
Each individual component of a muntin is referred to as a bar. The muntin bars may be formed of wood, vinyl, aluminum or the like. These muntin bars are cut to the appropriate size and shape, and then are affixed to one another to form the desired window style, such as a colonial or divided lite-style window. The technique most commonly used to affix a muntin to the window is a double-sided adhesive tape, similar to the glazing tape used to secure glazing to its frame or sash. The tape used for muntin applications typically includes a high tack adhesive on both sides of a carrier, and a release liner that covers the adhesive on one side of the tape. The side of the tape without the release liner is secured to the surface of the muntin bars, usually during assembly, and the side with the release liner faces away from the muntin bars and is exposed. The release liner remains in place until installation of the muntin, at which time it is removed from the muntin bars for affixation of the muntin to the glass. The use of such adhesive tapes permits rapid assembly of windows and doors.
A prior art apparatus for applying tape is disclosed in U.S. Pat. No. 5,354,410, assigned to the assignee of the present application. This apparatus is not automated, and can handle only one member at a time.
The present invention represents an improvement over prior art apparatus and provides a substantially fully automated tape applicator for the members of a frame or sash for glazing and for muntin bars. The frame members, sash members, or muntin bars (hereinafter members) are advanced through the apparatus, tape is applied to each member, and the tape is cut automatically adjacent the end of each member without any manual intervention.
In one aspect of this invention, a feed mechanism, such as a drive roller, advances the members sequentially through the apparatus. Each member is pushed by members immediately thereafter. Tape is dispensed onto the members and a first pressure roller urges the tape against the members to firmly apply the tape. Guide mechanisms guide the members through the apparatus and a cutter cuts the tape adjacent a trailing edge of each member. In another aspect, the tape is dispensed from a roll upstream of the drive roller and the first pressure roller and is guided to the member by a tape guide roller. In another aspect, the first pressure roller urges the members against the drive roller to propel them through the apparatus.
In yet another aspect of the invention, a tape cutting mechanism cuts the tape automatically adjacent the trailing end of each member as the member passes through the apparatus. As the trailing end of each member reaches a predetermined location, a cutting blade is automatically actuated for cutting the tape.
In a preferred embodiment, the tape cutting mechanism of this invention includes a switch and an arm extending from the switch that projects through an opening in the table downstream of the drive roller. The tip of the arm preferably is provided with a roller, the top edge of which extends slightly above the top surface of the table. The top surface of the table in the vicinity of the switch is recessed slightly below the top surface of the table upstream of the switch adjacent to the drive roller. Downstream of the switch is a second pressure roller which urges the member against the top surface of the table. As the member passes from the elevated section of the table adjacent the drive roller, to the recessed section of the table adjacent the switch, the member is spaced slightly above the top surface of the table, and does not engage the roller on the switch arm. As the member continues its advancement, the forward end is urged downwardly against the top surface of the recessed section of the table by the second pressure roller. Initially, the trailing edge of the member rests on the elevated section of the table upstream of the switch, so that the member is disposed at an angle, and is spaced above the roller of the switch arm. As the frame member is advanced farther, the trailing edge eventually drops onto the recessed table section. At this point, the switch arm is pushed downwardly, activating the switch. A signal from the switch causes the apparatus to temporarily stop advancement of the member, and actuates the cutting blade, which drops onto the member and cuts the tape adjacent the trailing end of the member. The blade is then raised. The cutting blade preferably is operated by a pneumatic cylinder or the like. A timer resets the apparatus, allowing the apparatus to continue its operation.
In yet another further aspect of the invention, the position of the cutting mechanism is adjustable with respect to the feed direction to permit the cutting blade to be positioned to cut the tape at the desired location with respect to the trailing edge of a member.
In yet another further aspect of the invention, multiple rollers are provided for guiding the member to and past the first pressure roller, and the cutting mechanism.
In the method of this invention, members are advanced sequentially through an apparatus in a feed direction. Tape is fed to each member and is urged against each member to form an adhesive bond. The tape is then automatically cut adjacent a trailing edge of each member. In one aspect of the method of this invention, advancement of the members is temporarily stopped while the tape is being cut. In another aspect of the method, a single drive roller advances each of the members.